Sulfasalazine intensifies temozolomide cytotoxicity in human glioblastoma cells

Author(s)

Ignarro, Raffaela Silvestre ^[1] ; Facchini, Gustavo ^[1] ; Vieira, Andre Schwambach ^[2] ; De Melo, Daniela Rodrigues ^[3] ; Lopes-Cendes, Iscia ^[2] ; Castilho, Roger Frigerio ^[3] ; Rogerio, Fabio ^[1]

Affiliation

^[1] State Univ Campinas UNICAMP, Dept Anat Pathol, Fac Med Sci, Av Tessalia Vieira De Camargo 126, BR-13083887 Campinas, SP - Brazil

^[2] State Univ Campinas UNICAMP, Dept Med Genet, Fac Med Sci, Av Tessalia Vieira De Camargo 126, BR-13083887 Campinas, SP - Brazil

^[3] State Univ Campinas UNICAMP, Dept Clin Pathol, Fac Med Sci, Av Tessalia Vieira De Camargo 126, BR-13083887 Campinas, SP - Brazil

• Document type: Journal article
• Source: Molecular and Cellular Biochemistry; v. 418, n. 1-2, p. 167-178, JUL 2016.
• Web of Science Citations: 6

Abstract

Temozolomide (TMZ) is an alkylating agent used to treat glioblastoma. This tumor type synthesizes the antioxidant glutathione through system X (c) (-) , which is inhibited by sulfasalazine (SAS). We exposed A172 and T98G human glioblastoma cells to a presumably clinically relevant concentration of TMZ (25 A mu M) and/or 0.5 mM SAS for 1, 3, or 5 days and assessed cell viability. For both cell lines, TMZ alone did not alter viability at any time point, while the coadministration of TMZ and SAS significantly reduced cell viability after 5 days. The drug combination exerted a synergistic effect on A172 cells after 3 and 5 days. Therefore, this particular lineage was subjected to complementary analyses on the genetic (transcriptome) and functional (glutathione and proliferating cell nuclear antigen (PCNA) protein) levels. Cellular pathways containing differentially expressed genes related to the cell cycle were modified by TMZ alone. On the other hand, SAS regulated pathways associated with glutathione metabolism and synthesis, irrespective of TMZ. Moreover, SAS, but not TMZ, depleted the total glutathione level. Compared with the vehicle-treated cells, the level of PCNA protein was lower in cells treated with TMZ alone or in combination with SAS. In conclusion, our data showed that the association of TMZ and SAS is cytotoxic to T98G and A172 cells, thus providing useful insights for improving TMZ clinical efficacy through testing this novel drug combination. Moreover, the present study not only reports original information on differential gene expression in glioblastoma cells exposed to TMZ and/or SAS but also describes an antiproliferative effect of TMZ, which has not yet been observed in A172 cells. (AU)

• FAPESP's process: 11/50400-0 - Mitochondrial energy metabolism, redox state and functionality in cell death and cardiometabolic and neurodegenerative disorders
• Grantee: Aníbal Eugênio Vercesi
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/07559-3 - BRAINN - The Brazilian Institute of Neuroscience and Neurotechnology
• Grantee: Fernando Cendes
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 13/02618-1 - Analysis of the oxidative stress induced by sulfasalazine associated with temozolomide in human and rat glioma cells
• Grantee: Fábio Rogério
• Support Opportunities: Regular Research Grants